1. Field of the Invention
The present invention relates to a medical instrument for examining newborn babies and more particularly to a calibrated optical-electro instrument for objectively determining the degree of jaundice in newborn babies.
2. Description of the Prior Art
The medical profession is aware of the importance of determining the existence of jaundice immediately after the birth of a baby. A large number of newborn children exhibit some degree of jaundice and frequently a jaundice test is performed as a regular routine in the delivery room. The degree of jaundice can range from a physiologically permissible level which will disappear within a short period of time after the birth to various severe degrees of jaundice, progressing to nuclear jaundice which can result in the death of a newborn or cerebral palsy as sequela even when the child is saved from death. While an accurate examination of the intensity of the jaundice condition can be determined by a measurement of the bilirubin value of the blood serum taken from newborns, it can be rather difficult or is often even unnecessary to take blood from each and every newborn for this measurement. Generally, doctors have made a visual observation of the color of the newborn's skin and then decided if there was any necessity to take a blood specimen for measurement of the bilirubin value of the blood serum.
To assist the doctors in making this visual observation the Gosset Icterometer has been developed and is employed as a screening test for deciding whether there is a need to test the bilirubin value of the blood serum. Basically, the Gosset Icterometer utilizes a plurality of standard color strips that are pressed against the skin of the baby and visually matched. Problems existed, however, due to the spectral reflection factors of the yellowish reference strips on the Icterometer, particularly under artificial illumination. Accordingly, although the prior art Icterometer has been of great assistance to the medical profession as a preliminary screening method, it frequently was necessary to rely upon the actual measurements of bilirubin in the blood serum from simply a safety point of view. Thus, quite frequently there are occasions of drawing blood from newborns that are in good health.
Of interest to the present invention is the work of Ballowitz and Avery, "Spectral Reflectance of the Skin", Biol. Neonate 15: 348-360 (1970) and U.S. Pat. No. 4,029,085. Cited of general interest are several patent disclosures relating to oximeters such as U.S. Pat. No. 3,638,640; U.S. Pat. No. 3,677,648; U.S. Pat. No. 3,814,081 and U.S. Pat. No. 3,998,550.
Accordingly, there is still a demand in the prior art to provide a safe and reliable objective test to determine the degree of jaundice in newborn babies.